Physics in the DLR Test: Formulas and Prep

Alongside English and technical comprehension, physics is one of the knowledge tests in the DLR aptitude assessment (the "Grunduntersuchung" used by SWISS, Lufthansa/EFA and other airlines and flight schools). For many candidates, this is the section that causes the most worry, especially if school-level formulas feel like a distant memory. The good news: the level sits somewhere between lower-secondary and upper-secondary school, and with a clear structure the material can be refreshed in a manageable amount of time.

This article gives you an overview of the topics typically covered, the key formulas written out in plain notation, and a few small worked examples to follow along with. You'll also find tips on using the PHY module in DLR Exam Trainer to refresh your knowledge efficiently, and how to stay consistent without drowning in formula sheets. If you're still unsure how the whole assessment is structured, it's worth reading the DLR test: the complete guide first.

What is the PHY test?

PHY refers to the physics section of the knowledge tests. It's assessed as multiple choice, usually with four answer options, staying close to formulas and everyday physical situations. It's not about freely deriving complex equations — it's about understanding basic physical relationships and applying them: why an object moves the way it does, what happens in a simple circuit, how pressure and surface area relate to each other.

Content-wise, the test typically covers:

• Mechanics: forces, acceleration, energy (kinetic and potential), pressure, density
• Electricity: Ohm's law, series and parallel circuits, electrical power
• Magnetism: basic principles, simple applications
• Optics: reflection, refraction, lenses
• Thermodynamics: temperature, thermal expansion, states of matter
• Waves: frequency, wavelength, propagation

The level roughly matches what's taught between lower-secondary school and the end of upper-secondary school — nothing that requires a physics degree, but enough that rusty school knowledge needs to be reactivated.

Format and procedure

On test day, PHY runs like the other knowledge tests: a multiple-choice test on screen or on paper, depending on the location and current procedure. You read a question, typically choose from four answer options, and pick the correct one. There's no free-text field and no lengthy derivation — you either have the formula in mind or can work it out from context, then do a short calculation or apply logical reasoning.

The exact number of questions, time allowed, and whether PHY is even part of your specific appointment depends on the procedure and airline in question — when in doubt, check with the organisation running the assessment or consult official materials. Typically, knowledge tests like PHY alternate with computer-based performance tests throughout the day, with breaks in between. The DLR test guide explains a full test day in more detail.

What really counts: how it's evaluated

For PHY, what counts is the number of correctly answered questions. The result is ultimately expressed as a rating (roughly A through D, depending on the procedure), not a raw percentage. The target is a rating of A or B — inside DLR Exam Trainer you'll see this reflected in a traffic-light indicator: green from around 80% correct, amber from around 65%. Below that, it's worth revisiting the weaker topic areas specifically, rather than simply practising more questions in a row.

It's important to understand there's no partial credit for "almost right." An answer option is either correct or it isn't. This also means that, when you're genuinely unsure, guessing is often statistically better than leaving a question unanswered — assuming the format even allows you to skip, which varies by procedure.

ImportantDon't rely on individual experience reports for exact scores or failure rates — procedures and standards can change. For binding information, only what the airline or DLR officially communicates counts.

Topic map: the key formulas in plain words

You don't need to memorise an entire formula sheet, but a solid basic toolkit helps enormously when you need to find the right approach quickly under time pressure. Here are the core formulas from the test in simple notation:

Mechanics

• Force equals mass times acceleration, so F = m·a
• Pressure equals force divided by area, so p = F/A
• Potential energy equals mass times gravitational acceleration times height, so E = m·g·h
• Density equals mass divided by volume, so ρ = m/V
• Speed equals distance divided by time, so v = s/t

Electricity

• Ohm's law: voltage equals resistance times current, so U = R·I
• Electrical power equals voltage times current, so P = U·I

These seven formulas cover a large share of the calculation-based questions. The rest tend to be conceptual questions (e.g. "What happens to total resistance when you add a resistor in parallel?") rather than pure calculations.

Example 1: Force and acceleration

An object with a mass of 10 kg is accelerated at 2 m/s². What force is acting on it?

F = m·a = 10 kg × 2 m/s² = 20 newtons.

Example 2: Ohm's law

A resistor of 5 ohms carries a current of 2 amperes. What is the voltage?

U = R·I = 5 Ω × 2 A = 10 volts.

Example 3: Pressure

A force of 100 newtons acts on an area of 0.5 m². What is the pressure?

p = F/A = 100 N / 0.5 m² = 200 pascals.

Solving small calculations like these in your head, or with a couple of intermediate steps, is exactly what the test asks for — no more, but no less either.

The most common mistakes

Confusing formulas instead of understanding them

If you memorise formulas by rote without understanding what each quantity (and its unit) represents, it's easy to mix up F = m·a with p = F/A, or U = R·I with P = U·I under pressure. If you understand why a formula looks the way it does, you'll recognise the right approach even when a question is phrased in an unfamiliar way.

Ignoring units

A common source of errors: values in different units (centimetres instead of metres, grams instead of kilograms) aren't converted before calculating. The result then comes out wrong by orders of magnitude.

Mixing up series and parallel circuits

A classic mistake: in a series circuit, resistances add up; in a parallel circuit, total resistance decreases. Mixing these up leads to systematically wrong answers on circuit questions.

Spending too much time on individual questions

If you get stuck puzzling over one unclear question for minutes, you lose time on questions you'd otherwise answer confidently. Better: quickly assess whether a formula is within reach — if not, move on and come back later if the format allows it.

Getting thrown off by distractors

Multiple-choice options often include plausible wrong answers on purpose (a number from a swapped formula, or the wrong unit). If you don't actually work through the calculation yourself and instead just "recognise" a number, it's easy to fall into this trap.

Concrete training tips

Build your own formula card

Write out the seven core formulas above by hand on a card, along with their units. Actively writing things down cements them better than just reading. Keep the card somewhere visible or snap a photo of it on your phone.

Refresh one topic block at a time

Work through the material block by block: mechanics first, then electricity, heat, optics, magnetism, waves. One block per short study session is usually enough — better to do it often and briefly than rarely and for a long time.

Look for everyday examples

Connect formulas to everyday situations: why does a balloon sink when the air gets colder? Why does a snowshoe press into snow less than a regular shoe? Images like these stick better than raw numbers.

Run short quiz sessions regularly

Rather than cramming once for a long time, work in short, regular rounds of multiple-choice questions — for example in DLR Exam Trainer, where the PHY module generates a new exercise every time, so you keep reinforcing concepts instead of memorising individual questions.

Review your mistakes properly

When a question goes wrong, don't just glance at the correct answer — work through the whole calculation yourself again. That way you understand the mistake instead of simply overwriting it.

Combine it with technical knowledge

Physics and technical comprehension often overlap (levers, forces, simple machines). Practising both modules in parallel pays off twice — more on that in the article on technical comprehension.

How to build PHY into your preparation

In DLR Exam Trainer, PHY is one of the modules included after a short trial period as part of the Pro subscription. The app shows you right after each session how many questions you answered correctly, and classifies your result with a traffic-light indicator: green from around 80%, amber from around 65%, red below that. This gives you an at-a-glance sense of whether a topic block already feels solid or whether you need to go over it again.

It makes sense not to practise PHY in isolation but to embed it into a broader rhythm that also covers the other knowledge and performance tests. A template for that is available in the 8-week training plan. Once you want to see how PHY performs alongside all the other modules under realistic time pressure, you can later use the full exam simulation, which runs through all modules back to back in the real order.

Plan for a few weeks of short, regular sessions on PHY rather than cramming everything into the last few days — physics fundamentals need a bit of time to become reliably retrievable again, but they're very trainable.